Field of the Disclosure
The present disclosure relates to a liquid crystal display device, and more particularly, to a liquid crystal display device having touch and three-dimensional image display functions, and a method for manufacturing the same.
Discussion of the Related Art
In keeping with dramatic advances in information technology, displays to visualize electronic information signals have been rapidly developed. Various slim, lightweight, and low-power flat display devices are commonly used as alternatives to conventional cathode ray tubes (CRTs).
Examples of flat display devices include liquid crystal displays (LCDs), plasma display panels (PDPs), field emission displays (FEDs), electroluminescent displays (ELDs) and the like. These flat display devices necessarily require a flat display panel to realize an image wherein the flat display panel has a structure in which a pair of transparent insulating substrates are joined such that an inherent luminous or polarized material layer is interposed between the substrates. Among flat display devices, liquid crystal display devices control light transmittance of liquid crystals using an electric field to display an image. For this purpose, an image display device includes a display panel including liquid crystal cells, a backlight unit to irradiate light to the display panel and a driving circuit to drive the liquid crystal cells.
The display panel is formed such that a plurality of gate lines cross a plurality of data lines to define a plurality of unit pixel regions. The display panel includes a thin film transistor array substrate and a color filter array substrate that face each other, a spacer interposed between the thin film transistor array substrate and the color filter array substrate to maintain a predetermined cell gap, and a liquid crystal inserted into the cell gap.
The thin film transistor array substrate includes a plurality of gate lines and a plurality of data lines, a thin film transistor formed as a switching device at each intersection between the gate line and the data line, a pixel electrode arranged in each liquid crystal cell and connected to the thin film transistor, and an orientation film coated on the resulting structure. The gate lines and data lines receive signals from driving circuits through respective pad portions.
In response to scan signals supplied to the gate lines, the thin film transistor transfers pixel voltage signals from the data lines to the pixel electrode.
In addition, the color filter array substrate includes color filters arranged in respective liquid crystal cells, a black matrix to partition the color filters and reflect external light, a common electrode to supply a reference voltage to the liquid crystal cells, and an orientation film coated on the resulting structure.
The thin film transistor substrate and the color filter array substrate thus separately formed are arranged and then joined such that the two substrates face each other, liquid crystal is injected into a region provided between the substrates and the region is sealed, thereby completing fabrication of the liquid crystal display device.
There is an increasing need for the liquid crystal display device thus fabricated including a touch panel, wherein a predetermined portion is touched by the hand or a separate input means and separate data can be transferred in response to the touch, and a three-dimensional image display panel to display a three-dimensional image. The touch panel and the three-dimensional image display panel are applied to the liquid crystal display by adhering the same to the outer surface of the liquid crystal display.
A conventional liquid crystal display wherein a touch panel and a three-dimensional image display panel are mounted on a liquid crystal display device will be described with reference to the annexed drawings.
FIG. 1 is a sectional view illustrating a conventional liquid crystal display device including a touch panel and a three-dimensional image display panel.
As shown in FIG. 1, the conventional liquid crystal display device including the touch panel and the three-dimensional image display panel broadly includes a liquid crystal panel 50, a three-dimensional image display panel 60 and a touch panel 70 formed in this order from the bottom. The liquid crystal panel 50, the three-dimensional image display panel 60 and the touch panel 70 are adhered to one another through a first adhesive layer 55 and a second adhesive layer 65. Here, the first and second adhesive layers 55 and 65 comprise double-sided adhesives.
The liquid crystal panel 50 includes first and second substrates 10 and 20 that face each other, a liquid crystal layer 25 filled between the first and second substrates 10 and 20, color filter layers 21 (21a, 21b, 21c) formed on the second substrate 20, and a first polarizing plate 31 and a second polarizing plate 32 formed on the outer surfaces of the first and second substrates 10 and 20.
Also, the three-dimensional image display panel 60 includes a third substrate 41 provided with electrodes made of a transparent material, a fourth substrate 42 provided with a black matrix layer (not shown), and a liquid crystal layer 45 filled between the third and fourth substrates.
An inner configuration of the touch panel layer 70 is changed into various forms according to driving mode of the touch panel.
The conventional liquid crystal display device including a touch panel and a three-dimensional image display panel have the following problems.
First, as described above, the three-dimensional image display panel and the touch panel are adhered to the liquid crystal display device through an adhesive, thus increasing a thickness and a weight of the liquid crystal display.
Second, the respective panels should be adhered through an adhesive, thus making the overall manufacture process complicated.
Third, the respective panels use separate substrates and the overall process is complicated, thus increasing manufacture costs.